JP4796934B2 - Sheet processing apparatus and image forming apparatus having the same - Google Patents

Description

  The present invention relates to a sheet processing apparatus that is attached to an image forming apparatus and the like and performs sorting, binding, stacking, and the like of printed sheets discharged from the apparatus, and an image forming apparatus that includes the sheet processing apparatus integrally or separately.

Accepts printed sheets sent from the discharge unit of the image forming apparatus built in or outside the sheet processing apparatus, stacks them on the staple tray, staples them to a predetermined number of sheet bundles using staple means, and discharges the sheets. In a sheet processing apparatus that discharges a sheet to a tray, in order to staple the sheet bundle at a predetermined position with high accuracy, the trailing edge of the sheet bundle is aligned and aligned on the staple tray, and staple binding is performed. Carrying is done.
When the trailing edge of the sheet bundle is aligned by the trailing edge fence, in order to improve the alignment of the sheet bundle, the discharge is used as a sheet bundle conveying unit that discharges the sheet bundle from the staple tray in the sheet discharge direction. At the back of the claw, the front end of the sheet bundle is pressed toward the rear end fence, the rear end of the sheet bundle is abutted against the rear end fence, the rear end is aligned, and the front end is aligned and aligned. A sheet processing apparatus that conveys a sheet bundle has been proposed (see, for example, Patent Document 1).
JP 2005-60106 A

However, in the sheet processing apparatus described in Patent Document 1, when aligning the front end of the sheet bundle, the sheet nail is released by the release nail in order to press the front end of the sheet bundle toward the rear end fence on the back surface of the release nail. After transporting from the trailing edge fence, it is necessary to move to the receiving position for the next sheet and wait for it to be put in the staple tray. There was a problem that the productivity to produce decreased.
The present invention has been made in consideration of the above circumstances, and improves the productivity of sheet bundles by reducing the waiting time for loading sheets into a tray for storing sheets such as a staple tray as much as possible. It is an object of the present invention to provide a sheet processing apparatus and an image forming apparatus including the sheet processing apparatus.

In order to solve the above-mentioned problem, the invention described in claim 1 includes a conveying unit that conveys a sheet, a stacking tray that stacks sheets conveyed to the conveying unit, and a sheet of sheets stacked on the stacking tray. In the sheet processing apparatus, comprising: an alignment member that abuts and aligns the leading end in the conveyance direction; and a discharge member that abuts and discharges the aligned bundle of sheets to the rear end of the sheet conveyance direction. The alignment belt is provided on the alignment belt so as to be able to circulate between the sheet receiving position of the stacking tray and the retracted position on the back side of the stacking tray, and the discharge member is provided on a discharge belt that moves in the direction of discharging sheets. While the sheet bundle is being discharged by the discharge member, the alignment member is moved from the rear end side of the sheet bundle to the receiving position, and is moved to the stacking tray by the conveying means. Characterized by a can accept over preparative transport.
According to a second aspect of the present invention, in the sheet processing apparatus of the first aspect, the alignment belt is an endless belt stretched on the stacking tray, and the alignment member is rotated by the alignment belt. The sheet is circulated between a sheet receiving position and the retracted position .
The invention according to claim 3 is characterized in that the moving speed of the alignment belt is equal to or lower than the sheet discharge moving speed of the discharge belt .

According to a fourth aspect of the present invention, in the sheet processing apparatus according to any one of the first to third aspects, the alignment member includes a pressing unit that presses the leading end of the sheet bundle during alignment. And
Sheet processing device.
The invention according to claim 5 is the sheet processing apparatus according to claim 4, wherein the pressing means is an elastic member.

A sixth aspect of the present invention is an image forming apparatus comprising the sheet processing apparatus according to any one of the first to fifth aspects.

  According to the present invention, by adopting the above-described configuration, the waiting time for feeding a sheet to a tray for storing sheets such as a staple tray is shortened as much as possible to improve the productivity of the sheet bundle. It is possible to provide a sheet processing apparatus and an image forming apparatus including the sheet processing apparatus.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram showing a system configuration of an image forming apparatus including a sheet post-processing unit device and an image forming unit device as a sheet processing device according to an embodiment of the present invention. And a part of the image forming unit apparatus.

  In FIG. 1, a sheet post-processing unit device PD is attached to a side portion of the image forming unit device PR, and an image-formed sheet (recording medium) P discharged from the image forming unit device PR is a sheet post-processing device. Guided to PD. The sheet passes through a conveying path A having post-processing means for performing post-processing on one sheet (in this embodiment, a punch unit 100 as punching means), and a pair of conveying rollers (hereinafter simply referred to as conveying rollers) 2 3, 4, transport path B that leads to the upper tray 201, transport path C that leads to the shift tray 202 via transport rollers 2, 5, 6, transport rollers 7, 8, 9, 10, and staple discharge roller 11 The branching claws 15 and the branching claws 16 are configured to be distributed to a conveyance path D that leads to a processing tray F (hereinafter also referred to as a staple processing tray) that performs alignment, stapling, and the like. The tray surface on which the sheets of the staple processing tray F are stacked is inclined so that the downstream side in the conveyance direction of the sheet P discharged from the staple discharge roller 11 is upward, and the inclination angle is relative to the gravity direction. The angle is set to a minimum angle that does not interfere with the middle folding plate 74 on the lower side of the inclined surface and its driving mechanism and mechanisms such as the end surface binding stapler S1.

The sheet bundle PB guided to the staple processing tray F through the conveyance paths A and D and subjected to alignment, stapling, and the like in the staple processing tray F passes through a branch conveyance path I by a branch guide plate 54 and a guide member 44 described later. The transfer path C leading to the shift tray 202 is configured to be distributed to a processing tray G that performs folding or the like (hereinafter also referred to as a middle folding or saddle stitching processing tray), and the folding is performed on the middle folding processing tray G. The sheet passes through the conveyance path H and is guided to the lower tray 203. Further, a branching claw 17 is disposed in the conveyance path D and is held in the state shown in the figure by a spring (not shown). After the rear end of the sheet P passes through the conveyance roller 9, 10 and the staple discharge roller. 11 is configured such that at least the conveying roller 9 is reversed to guide the trailing edge of the sheet to the prestack path (sheet accommodating portion) E so that the sheet is retained and conveyed while being overlapped with the next sheet. Yes. By repeating this operation, two or more sheets can be stacked and conveyed.

In the common conveyance path A upstream of the conveyance path B, the conveyance path C, and the conveyance path D, an inlet sensor 301 that detects the sheet P received from the image forming unit apparatus PR, an inlet roller 1 and a punch unit downstream thereof. 100, punch and waste hopper 101, transport roller 2, branch claw 15 and branch claw 16 are sequentially arranged. The branch claw 15 and the branch claw 16 are held in the state shown in FIG. 1 by a spring (not shown), and when the solenoid (not shown) is turned on, the branch claw 15 rotates upward and the branch claw 16 rotates downward. Thus, the sheet is distributed to the conveyance path B, the conveyance path C, and the conveyance path D.
When the sheet is guided to the conveyance path B, the branch claw 15 is in the state of FIG. 1 and the solenoid is OFF. When the sheet is guided to the conveyance path C, the branch claw 15 is turned on by turning on the solenoid from the state of FIG. When the sheet is guided to the conveyance path D, the branch claw 16 is in the state of FIG. 1, the solenoid is OFF, and the branch claw 15 is in the state of FIG. By turning on the solenoid, the solenoid is turned upward.
In this sheet post-processing apparatus, punching (punch unit 100), sheet sorting (shift tray 202), sheet alignment and sheet end binding (tip tapping 512, end surface binding stapler S1), sheet, Alignment, saddle stitching, and middle folding (tip hitting 512, saddle stitching stapler S2, folding plate 74, folding roller 81) and the like can be performed.

  In this embodiment, the image forming unit apparatus PR performs optical writing on an image forming medium such as a photosensitive drum based on input image data to form a latent image on the surface of the photosensitive drum, and the formed latent image. Is an image forming unit device using a so-called electrophotographic process in which toner is developed, transferred to a recording medium such as a sheet, fixed and discharged, and the image forming device itself using the electrophotographic process is well known. Description and illustration of the detailed configuration will be omitted. In this embodiment, an image forming unit device using an electrophotographic process is illustrated, but a system using a known image forming device such as an inkjet or a printing machine and a printing machine (printer) may be used. Needless to say.

Next, the processing of (1) sheet sorting, (2) sheet alignment and sheet edge binding, and (3) sheet alignment, saddle stitching, and middle folding processing by the sheet post-processing apparatus according to the present embodiment will be described in detail. A description will be given together with a typical configuration.
(1) Sheet Sorting Process The sheet sorting process for sheets P or sheet bundles PB is a predetermined number of sheets (or sheet bundles PB formed on the sheet P or processing tray F conveyed via the conveying path A and the conveying path C (or In this process, the shift discharge roller 6, the return roller 13, the paper surface detection sensor 330, the shift tray 202, and the lifting mechanism of the shift tray 202 shown in FIG. And a swing mechanism of the shift tray 202 shown in FIG.

  In FIG. 3, reference numeral 13 denotes a sponge return roller for contacting the sheet P discharged from the shift sheet discharge roller 6 and abutting the rear end of the sheet P against an end fence 32 (not shown). The return roller 13 is rotated in the direction of arrow A by the rotational force of the shift paper discharge roller 6 and conveys the sheet P in the direction opposite to the discharge direction of the sheet P. A tray lift limit switch 333 is provided in the vicinity of the return roller 13. When the shift tray 202 is lifted and the return roller 13 is pushed up, the tray lift limit switch 333 is turned on and the tray lift motor 168 is stopped. Thereby, overrun of the shift tray 202 is prevented.

  As shown in FIG. 1, a paper surface detection sensor 330 is provided in the vicinity of the return roller 13 as paper surface position detecting means for detecting the paper surface position of the shift tray 202. Although not shown in FIG. 1, the paper surface detection sensor 330 includes the paper surface detection lever 30 shown in FIG. 3, a paper surface detection sensor (for stapling) 330a, and a paper surface detection sensor (for non-staple) 330b. The paper surface detection lever 30 is provided so as to be rotatable about its shaft portion 30c, and has a contact portion 30a that contacts the upper surface of the rear end of the sheet P stacked on the shift tray 202 and a fan-shaped shielding portion 30b. Yes. The paper surface detection sensor (for stapling) 330a positioned above is mainly used for staple paper discharge control, and the paper surface detection sensor (for non-staple) 330b is mainly used for shift paper discharge control. In the present embodiment, the paper surface detection sensor (for stapling) 330a and the paper surface detection sensor (for non-staple) 330b are turned on when being blocked by the shielding portion 30b. Accordingly, when the shift tray 202 is raised and the contact portion 30a of the paper surface detection lever 30 is rotated upward, the paper surface detection sensor (for stapling) 330a is turned off, and when further rotated, the paper surface detection sensor (for non-staple) 330b is operated. Turn on. When it is detected by the paper surface detection sensor (for stapling) 330a and the paper surface detection sensor (for non-stapling) 330b that the sheet stacking amount has reached a predetermined height, the shift tray 202 is lowered by a predetermined amount. Thereby, the paper surface position of the shift tray 202 is kept substantially constant.

<Shift tray up / down>
The lifting mechanism of the shift tray 202 will be described in detail. As shown in FIG. 3, the shift tray 202 moves up and down by driving the drive shaft 21 by a drive unit including a tray lifting / lowering motor 168, a worm gear 25, and the like. A timing belt 23 is tensioned between the drive shaft 21 and the driven shaft 22 via a timing pulley. The side plate 24 supporting the shift tray 202 is fixed to the timing belt 23, and the unit including the shift tray 202 is suspended so as to be lifted and lowered by such a configuration. Power generated by a tray lifting / lowering motor 168 capable of forward / reverse rotation as a drive source for moving the shift tray 202 in the vertical direction is transmitted to the final gear of the gear train fixed to the drive shaft 21 via the worm gear 25. ing. Since the worm gear 25 is provided midway, the shift tray 202 can be held at a fixed position, and an accidental drop accident or the like of the shift tray 202 can be prevented.

  A shielding plate 24a is integrally formed on the side plate 24 of the shift tray 202, and a fullness detection sensor 334 for detecting the full load of stacked sheets and a lower limit sensor 335 for detecting a lower limit position are disposed below the shielding plate 24a. The full detection sensor 334 and the lower limit sensor 335 are turned on / off by 24a. The fullness detection sensor 334 and the lower limit sensor 335 are photosensors, and are turned on when blocked by the shielding plate 24a. In FIG. 3, the shift paper discharge roller 6 is omitted.

<Shift tray swing>
As shown in FIG. 2, the swing mechanism of the shift tray 202 rotates the shift cam 31 using a shift motor 169 as a drive source. A pin 31a stands on the shift cam 31 at a position away from the center of the rotation shaft, and guides the pin 31a and the rear end of the loaded paper on the shift tray 202, and fits in a direction orthogonal to the sheet discharge direction. The end fence 32 fitted in the end fence 32 is fitted, and the end fence fitted with the pin 31a is moved in the direction orthogonal to the sheet discharge direction by the rotation of the shift cam 31 and shifted accordingly. The tray 202 also moves. The shift tray 202 stops at two positions, the front and the back. The stop position is determined by turning on and off the shift motor 169 when the shift sensor 336 detects the recess 31c of the detection plate 31b that rotates together with the shift cam 31. The

The shift paper discharge roller 6 has a drive roller 6a and a driven roller 6b. As shown in FIGS. 1 and 4, the driven roller 6b is supported on the upstream side in the sheet discharge direction, and is rotatably provided in the vertical direction. The open / close guide plate 33 is rotatably supported at a free end portion. The driven roller 6b contacts the driving roller 6a by its own weight or urging force, and the sheet P is nipped between the rollers 6a and 6b and discharged. When the bound sheet bundle PB is discharged, the open / close guide plate 33 is rotated upward and returned at a predetermined timing. This timing is based on a detection signal of the shift paper discharge sensor 303. Determined. The stop position is determined based on the detection signal of the paper discharge guide plate opening / closing sensor 331 and is driven by the paper discharge guide plate opening / closing motor 167.
As described above, the shift tray 202 is swung in the left-right direction for every predetermined number of sheets or every predetermined number of sheets, and the sheets P or the sheet bundles PB stacked on the shift tray 202 are shifted and stacked, and the sheets are sorted in a deliberate manner. Can do.

(2) Sheet alignment and stapling process Next, when the sheet P conveyed via the conveyance path D is stacked on the processing tray F to produce the sheet bundle PB, the end and center of the subsequent sheet bundle PB In order to perform these processes with high accuracy in the stapling process at the center and the middle folding process at the center of the sheet bundle PB, the leading and trailing ends of the sheet bundle PB must be stacked (aligned). It is desirable to perform this matching process.

<Sheet alignment processing>
The configuration of the processing tray F that performs the stapling process will be described with reference to FIGS. As shown in FIGS. 5 and 6, the sheet P sandwiched and conveyed by the driving roller a and the driven roller 22 b of the staple discharge roller 11 rises in the direction of arrow C along the substrate 64 of the processing tray F, and the sheet P The conveyance direction is changed from the direction of the arrow C to the direction of the arrow D by the weight of P, and the stacking is sequentially performed on the rear end fence 51 of the processing tray F. In this case, the alignment of the sheets P having different sheet lengths when the sizes are mixed and the like is performed in the vertical direction (sheet conveyance direction) by the hitting roller 12, as shown in FIG. The hitting roller 12 is given a pendulum motion by a hitting solenoid (SOL) 170 around the fulcrum 12a, and intermittently acts on the sheet sent to the processing tray F to hit the sheet against the rear end fence 51. The hitting roller 12 rotates counterclockwise (arrow B direction). As shown in FIG. 7, the sheet bundle PB stacked in this way is provided on two tip tapping belts 511 arranged in parallel with a discharge belt 52 that conveys the aligned sheet bundle PB upward. Alignment in the vertical direction (sheet conveyance direction) is performed by the two hitting tips 512, and alignment in the horizontal direction (sheet width direction orthogonal to the sheet conveyance direction) is performed by the jogger fence 53.

As shown in FIGS. 7 and 8, the discharge belt 52 is formed in an endless shape, and has two discharge claws 52a that hold the sheet bundle PB on the surface thereof and convey it upward (conveying direction) at a predetermined interval. It is attached and stretched between the drive pulley 52b and the driven pulley 52c. Accordingly, as the drive pulley 52b rotates, the discharge belt 52 moves on the conveyance path J in the direction of arrow E, and the discharge claw 52a also moves on the conveyance path J in the direction E to move the sheet bundle PB upward. Transport.
On the other hand, a tip tapping belt 511 is also formed in an endless shape, and two tip tapping 512 for aligning the tip P1 of the sheet P are attached to the surface thereof at a predetermined interval, and a driving pulley 511a that is driven to rotate by a motor (not shown). It is stretched around the driven pulley 511b. In this case, each of the tip tapping 512 attached to the two tip tapping belts 511 is attached at the same position in the moving direction of the tip tapping belt 511, and when the tip P1 of the sheet P abuts against these tip tapping 512. It is possible to contact evenly. The tip tapping belt 511 moves in the direction of arrow F (see FIGS. 8B and 8D) and the direction of G (see FIGS. 8A and 8F) by the rotation of the drive pulley 511a. As the tip tapping belt 511 moves, the tip tapping 512 also moves in the arrow F direction and the G direction.

  As shown in FIGS. 8A to 8F, the discharge pawl 52a and the leading edge 512 are moved in the G direction by the leading edge 512, and the sheet P is moved to the trailing edge fence 51. During the operation of aligning the leading end PB1 and the trailing end PB2 of the sheet bundle PB with the trailing end P2 being abutted (alignment state), the discharge claw 52a is retracted from the conveyance path J of the sheet bundle PB (FIG. 8A). )reference). When the alignment of the leading edge PB1 of the sheet bundle PB by the leading edge hit 512 is completed, the leading edge hit 512 moves upward (in the direction of arrow F) in accordance with the movement of the leading edge hitting belt 511, and further the conveyance path J of the sheet bundle PB. Is rotated to the back side of the sheet, stopped at the first predetermined position, and retracted from the conveyance path J of the sheet bundle PB (see FIG. 8B). Subsequently, in the state where the front end hit 512 is stopped at the first predetermined position, the discharge belt 52 (see FIG. 7) stretched between the two rear end fences 51 is rotated, and the rear end fence is thus rotated. The discharge claw 52a holds the rear end PB2 of the sheet bundle PB stacked on the sheet 51, and conveys the sheet bundle PB upward (in the direction of arrow E) on the conveyance path J (see FIG. 8C).

  Next, when the discharge claw 52a holding the sheet bundle PB rises on the conveyance path J and passes through the second predetermined position, the tip tapping 512 starts moving in the F direction, and conveys. From the path J, it appears on the transport path J from the retracted position and ascends (in the direction of arrow F) on the transport path J so as to follow the rear of the discharge claw 52a (see FIG. 8D). In this case, since the rising speed of the tip hit 512 is set to be equal to or lower than the rise speed of the discharge claw 52a, it is possible to prevent the tip hit 512 from colliding with the discharge claw 52a. The discharge claw 52a continues to rise (in the direction of arrow F) on the conveyance path J, but the tip hit 512 stops rising when it rises to a predetermined third position (FIG. 8E )reference). In this case, the third position is set to be larger than the acceptable sheet size so as to improve the productivity of the sheet bundle PB of all sizes. Simultaneously with the stop of the movement of the leading edge 512, the sheet P conveyed from the conveyance path D starts to be discharged onto the processing tray F by the staple discharge roller 11 (see FIG. 8E). While the discharge claw 52a moves up the conveyance path J, the tip tapping 512 stopped at the predetermined third position comes into contact with the front end P1 of the sheet P discharged by the staple paper discharge roller 11, and the sheet P The leading edge 512 is lowered (in the direction of arrow G) to the fourth predetermined position on the conveyance path J (see FIG. 8A), and the sheet P 6 is transferred in the direction D (see FIG. 6), and the trailing edge P2 of the sheet P is abutted against the trailing edge fence 51. This operation causes the predetermined number of sheets P to be discharged from the staple discharge roller 11 and the predetermined number of sheets P to be discharged. Is continued until the sheet P is stacked on the trailing edge fence 51. When a predetermined number of sheets P are stacked on the trailing edge fence 51 and a sheet bundle with the leading and trailing edges aligned is prepared, as will be described later, the sheet bundle Stay at the back of the PB Le processing is performed, the operation of the release pawl 52a and the tip tapping 512 shown in the aforementioned FIG. 8 (B) is started, thereafter, FIG 8 (C) and subsequent operations are repeated sequentially.

  In this way, the leading edge 512 moves to the home position (first position) on the back side of the processing tray F between the breaks of the job, that is, between the last sheet of the sheet bundle PB and the first sheet of the next sheet bundle PB. The end surface binding stapler S1 is driven by the staple signal from the control means 350, and the binding process is performed. The sheet bundle PB subjected to the binding process is immediately sent to the shift paper discharge roller 6 by the discharge belt 52 having the discharge claw 52a, and is discharged to the shift tray 202 set at the receiving position. At this time, the tip tapping 512 moves to the next sheet receiving position so as to follow the discharge claw 52a.

  As shown in FIG. 9, the home position of the discharge claw 52 a is detected by a discharge belt HP sensor 311, and this release belt HP sensor 311 is turned on by a discharge claw 52 a provided on the discharge belt 52.・ Turn it off. Two discharge claws 52a are arranged at opposing positions on the outer periphery of the discharge belt 52, and the sheet bundle PB stored in the processing tray F is moved and conveyed alternately. As shown in FIG. 7, the discharge belt 52 is disposed at the alignment center in the sheet width direction, and is driven by the discharge motor 157 via the drive shaft 52b and the pulley 52c. The discharge roller 56 is arranged and fixed at a symmetrical position around the discharge belt 52, and the peripheral speed of the discharge roller 56 is set to be higher than the peripheral speed of the discharge belt 52.

  Similarly to the HP sensor 311 of the discharge belt, the home tapping belt 511 is also detected by a sensor (not shown). Further, two tip tappings 512 are arranged at opposing positions on the outer periphery of the tip tapping belt 511, and the vertical alignment is alternately performed for each sheet bundle accommodated in the processing tray F. Further, the interval between the tip hits 512a and 512b is equal to or smaller than the horizontal size of the smallest sheet that can be received, so that the vertical alignment can be surely performed.

  Further, as shown in FIGS. 10A and 10B, the tip hitting 512 is provided with a fulcrum 512b at the tip of a support section 512a having a cross-sectional shape attached to a predetermined position of the tip hitting belt 511, and this fulcrum 512b. A tip hitting portion 512c is pivotally attached about the shaft, and a pressing means 512d made of an elastic member such as a spring is attached between the support portion 512a and the tip hitting portion 512c. Therefore, as described in FIGS. 8A and 8F, the leading edge P1 of the sheet P discharged from the staple discharge roller 11 contacts the leading edge hitting portion 512c, and the leading edge hit 512 is lowered in the direction of arrow G. When the rear end P2 of the sheet P is abutted against the rear end fence 51, the front end hitting portion 512c rotates upward against the elastic force of the pressing member 512d as shown in FIG. Then, the sheet P is pressed toward the substrate 64 side of the processing tray F, and the leading end P1 of the sheet P is aligned. Therefore, the front end P1 of the sheet P is less likely to come off from the front end hitting portion 512c, and appropriate front end alignment is possible.

  Next, a case where the side edges of the sheet P are aligned by the jogger fence 53 (alignment in the horizontal direction) will be described. As shown in FIG. 5, the jogger fence 53 is driven via a timing belt by a jogger motor 158 capable of forward and reverse rotation, and reciprocates in the sheet width direction (arrow H direction). Therefore, based on the sheet size signal from the image forming unit device PR and the sheet size signal detected by the sheet post-processing unit device PD, the jogger fence is in a state where the width is wider than the width of the conveyed sheet P. 53, when the sheet P is conveyed to the processing tray F, the jogger fence 53 is moved, the distance between the jogger fences 53 is narrowed, and the side edges of the sheets P put into the processing tray F are aligned. To do.

<Sheet edge presser of sheet bundle>
Next, a mechanism for pressing the bulge of the rear end of the sheet bundle loaded on the processing tray F will be described with reference to FIG. As described above, the sheet P discharged to the processing tray F is aligned in the vertical direction (sheet conveying direction) by the leading edge 512 for each sheet P, but the sheet trailing edge P2 stacked on the processing tray F is When curled or weak, the rear end tends to buckle and swell due to the weight of the sheet itself. Further, as the number of stacked sheets increases, the gap for the next sheet P in the trailing edge fence 51 is reduced, and the vertical alignment tends to be deteriorated. The trailing edge pressing lever 110 shown in FIG. 11 makes it easier for the sheet P to enter the trailing edge fence 51 by reducing the swelling of the trailing edge P2, and the trailing edge pressing lever 110 is moved back and forth in the direction of arrow I. It is movable.

  12A, 12B, 13C, and 13D show the sheet bundle PB, the stapler S1, the rear end fence 51, and the rear end pressing lever 110 when viewed from the direction of the arrow X in FIG. It is a figure which shows arrangement | positioning relationship and operation | movement relationship. The rear end pressing levers 110a, 110b, and 110c for pressing the rear end PB2 of the sheet bundle PB held by the rear end fence 51 are arranged at three locations on the front, center, and back so as to face the surface of the sheet bundle PB. Is arranged. Here, the mechanism of the rear end presser lever 110a in front will be described. First, since the rear end presser lever 110a is fixed to the timing belt 114a, and the timing belt 114a is interposed via the rear end presser lever motor 112 and the pulley 113, the rear end presser lever 110a is connected to the rear end presser lever motor. In accordance with the rotation of 112, it moves back and forth toward the sheet bundle PB. Further, the home position is detected by the convex portion 116a of the rear end presser lever 110a shielding the home sensor 111a. The home position of the trailing edge presser lever 110a is a position where the stapler S1 does not interfere with the stapler S1 within a range in which the stapler S1 moves in the arrow K direction (the width direction of the sheet P) as shown in FIG. The amount of movement in the direction of pressing the rear end of the sheet bundle PB, that is, the direction of the arrow I in FIG. 11, is determined by the number of input pulses to the rear end presser lever motor 112. It moves to the position where it touches the PB and suppresses the swelling of the trailing edge PB2 of the sheet bundle. The change in the thickness of the stacked sheet bundle PB is absorbed by the expansion / contraction operation of the spring 115a, and is configured to respond. The operations of the rear end presser levers 110b and 110c are the same as those of the rear end presser lever 110a.

  Next, the operation of the rear end presser levers 110a, 110b, and 110c in each binding mode will be described. 12B is the front binding position, FIG. 13C is the two-position binding, and FIG. 13D is the standby position of the stapler S1 when the back binding is performed. At each standby position, it is necessary to prevent interference with the stapler S1 when the rear end presser lever 110 is operated. At the time of front binding, the rear end presser levers 110b, 110c can be operated at the rear end presser levers 110a, 110b, 110c, and at the time of rear binding, the rear end presser levers 110a, 110b can be operated. 12B to 12D show the operation position of the rear end pressing lever in each binding mode. This operation timing is from when the discharged sheet is stacked in the trailing edge fence 51 and aligned in the sheet width direction by the jogger fence 53 until the next sheet is aligned by the leading edge 512 or the hitting roller 12. Between.

<Stapler binding>
As described above, after the sheet bundle PB is aligned in the processing tray F at the leading edge, the trailing edge, and the side edge, the aligned sheet bundle PB is stapled by the end surface binding stapler S1 at the trailing edge. The stapler S1 that performs this process will be described with reference to FIGS. As shown in FIG. 14, the end surface binding stapler S1 is driven via a timing belt by a stapler moving motor 159 capable of forward and reverse rotation, and the sheet width along the guide rod 65 in order to bind a predetermined position of the sheet bundle end portion PB2. Move in the direction. A stapler movement HP sensor 312 for detecting the home position of the end surface binding stapler S1 is provided at one end of the movement range, and the binding position in the sheet width direction is the amount of movement of the end surface binding stapler S1 from the home position. Controlled by As shown in FIG. 15, when stapling is performed obliquely at the trailing edge PB2 of the sheet bundle, an oblique motor 160, a gear, a pinion, and a rack gear are used to rotate the stapler S1 relative to the guide rod 65. The detection sensor 313 is used to incline at a predetermined angle.

  As described above, in the sheet post-processing unit device according to this embodiment, the sheets P conveyed from the conveyance path D are stacked on the processing tray F, and the front and rear ends of the sheets P are aligned to produce the sheet bundle PB. However, these operations are controlled by a computer to be described later, and this flow will be described with reference to the flowchart shown in FIG. First, it is determined whether an activation command has been received from the upstream device (step 1 (ST1)). If YES, the tip tapping 512, the jogger fence 53, the staple S1, and the discharge claw 52a are moved to the receiving position. (Step 2 (ST2)). Next, the acceptance of the sheet P into the processing tray F is started (step 3 (ST3)), and then it is determined whether or not the sheet P is the final sheet (step 4 (ST4)). The tip tapping 512 retreats to the home position after vertical alignment (step 5 (ST5)). Next, lateral alignment is performed by the jogger fence 53 (step 6 (ST6)), the sheet bundle trailing edge PB2 is pressed by the trailing edge pressing lever 110 (step 7 (ST7)), and the sheet bundle by the stapler S1. PB binding is performed (step 8 (ST8)), and the discharge operation of the sheet bundle PB by the discharge claw 52a is started (step 9 (ST9)), and the tip tap 512 is moved to the receiving position so as to follow the discharge claw 52a. Move (step 10 (ST10)). Then, it returns to step ST3 again and repeats the same step a predetermined number of times. On the other hand, in the case of NO in step ST4, for each sheet P, in the order of vertical alignment by tapping 512 (step 11 (ST11)) and horizontal alignment by jogger fence 53 (step 12 ( ST12)), the sheet bundle trailing edge PB2 is pressed by the trailing edge pressing lever 110 (step 13 (ST13)). When this operation becomes the final sheet of the sheet P, the process moves to the above-described step 5 (ST5), and the sheet bundle PB subjected to staple binding is produced.

  In this embodiment, staple binding is performed at the rear end of the sheet bundle PB. However, as will be described later, when performing saddle stitching, center folding processing, and the like, staple binding processing at the rear end is performed. Only the alignment process of the sheet bundle PB is performed. Further, as the alignment process, in the present embodiment, alignment of the front end, the rear end, the side end and the thickness direction of the sheet bundle PB is performed, but it is not necessary to perform all of these alignments. It is sufficient to just align the leading and trailing edges.

As described above, in the sheet processing apparatus according to the present invention, the leading edge and the trailing edge of the sheet bundle PB are aligned with the discharge claw 52a by the separate leading edge 512, and the leading edge 512 is retracted from the conveyance path J of the sheet bundle PB. After the radiation claw 52a is moved, the radiation claw 52a follows the radiation claw 52a and appears from the rear of the radiation claw 52a, so that the waiting time until the sheet P is loaded into the processing tray F can be shortened. This makes it possible to improve the productivity of the sheet bundle.
In addition, when the conveyance direction alignment unit follows the sheet bundle, the movement direction of the conveyance direction alignment unit is set to be equal to or less than the movement speed of the sheet bundle, so that collision between the conveyance direction alignment unit and the sheet bundle being conveyed is avoided. Can do.
In addition, since the bundle conveying direction aligning unit that has moved following the sheet bundle is stopped at the next sheet receiving position when the sheet bundle is conveyed, it is possible to wait for an immediate shift to the alignment operation of the next sheet. .

The leading edge hitting strikes against the trailing edge fence of at least two places of the paper and suppresses the inclination of the sheet P, so that a good alignment can be performed.
Since the width of at least two places where the tip strikes is less than or equal to the minimum width of the receiving sheet, small-sized sheets can be reliably aligned.
Since the leading edge hitting portion is moved, even if the sheet is pressed too much, the leading edge hits away and the sheet can be protected from scratches.
Since the elastic member is provided for the tip hit, the tip hit can be returned to the normal position.
Since the leading edge is moved in the direction in which the sheet P is pressed against the staple tray, the sheets P can be reliably pressed and aligned.
Since the movable range of the tip tap is larger than the size of the receiving sheet, all the sizes that can be received can be arranged.
Since the leading edge is retracted to the back side of the conveyance path J, the operability can be improved.

  Next, in the sheet post-processing unit apparatus according to the present embodiment, the sheet bundle PB having the leading end and the trailing end aligned as described above is saddle-stitched from the processing tray F and conveyed to the middle folding processing tray G. Alternatively, conveyance from the processing tray F to the shift tray 202 is possible. A change in the conveyance direction of the sheet bundle PB will be described.

<Change of sheet bundle conveyance direction>
FIGS. 17A, 17 </ b> B, 18 </ b> C, and 18 </ b> D are diagrams illustrating a schematic configuration and operation of a sheet bundle conveyance direction changing unit according to the present embodiment. The conveying path J for feeding the sheet bundle PB from the edge binding processing tray F to the saddle stitching processing tray G and from the edge binding processing tray F to the shift tray 202 and the conveying means for conveying the sheet bundle PB shown in FIG. As shown in FIG. 6A, a conveying unit 35 that applies a conveying force to the sheet bundle PB, a discharge roller 56 that turns the sheet bundle PB, and a guide member 44 that guides the turn portion of the sheet bundle PB. The roller 36 of the conveying means 35 is configured such that the drive of the drive shaft 37 is transmitted by a timing belt 38, the roller 36 and the drive shaft 37 are connected and supported by an arm 39, and can move with the drive shaft 37 as a rotation fulcrum. It has a configuration. The rotation movement of the roller 36 of the conveying means 35 is performed by a cam 40. The cam 40 rotates around a rotation shaft 41, and the drive is transmitted from the motor M1.

  Here, when the sheet bundle PB is sent from the edge binding processing tray F to the saddle stitching processing tray G, as shown in FIG. 17B, the trailing edge PB2 of the sheet bundle PB aligned in the edge binding processing tray F is discharged. The sheet bundle PB is sandwiched between the roller 36 of the conveying means 35 and the driven roller 42 facing the roller 36 of the conveying means 35 to give a conveying force. At this time, the roller 36 of the conveying unit 35 stands by at a position where the sheet bundle leading end PB1 does not contact the roller 36. Here, as shown in FIG. 19, a surface 64 and a roller 36 on which the sheet bundle PB is guided when aligned on the edge binding processing tray F, or on which the sheet bundle PB is guided when pushed up by the release / release claw 52a. The distance L1 is made larger than the maximum sheet thickness L2 of the sheet bundle PB sent from the edge binding processing tray F to the saddle stitching processing tray G, and collision between the sheet bundle leading end PB1 and the roller 36 is avoided. Since the thickness of the sheet bundle varies depending on the number of sheets to be aligned in the edge binding processing tray F and the paper type, the minimum position where the roller 36 avoids collision with the leading end of the sheet bundle also varies. Therefore, if the retreat position is changed according to the information on the number of sheets and the paper type, the movement time from the retreat position to the position where the conveying force is applied can be minimized, which is advantageous for the productivity of the sheet bundle PB. Become. The information on the number of sheets and the paper type may be job information from the image forming unit device PR, or may be obtained by a sensor in the sheet post-processing unit device PD. However, when an unexpected large curl is generated in the sheet bundle PB aligned in the end binding processing tray F, the sheet bundle leading end PB1 and the roller 36 come into contact when the sheet bundle PB is pushed up by the discharge claw 52a. In some cases, it is necessary to provide a guide 47 just before the roller 36 as shown in FIG. 20 so that the contact angle between the sheet bundle leading end PB1 and the roller 36 is small. This guide 47 can obtain the same effect whether it is a fixed member or an elastic member.

  Next, as shown in FIG. 18C, after the sheet bundle front end PB1 has passed, the rollers 36 of the conveying means 35 are brought into contact with the surface of the sheet bundle PB to give a conveying force. At this time, the guide member 44 and the discharge roller 56 form a turn guide, and the sheet bundle is conveyed to the downstream saddle stitching processing tray G. When a sheet bundle is fed from the edge binding processing tray F to the shift tray 202, as shown in FIG. 18D, the guide member 44 is rotated, and the conveyance path connected to the shift tray 202 by the guide member 44 and the guide plate 46. Form. Then, the rear end PB2 of the sheet bundle PB aligned on the end binding processing tray F is pushed up by the discharge claw 52a and conveyed to the shift tray 202. In the present invention, the discharge roller 56 may be a driven roller that follows the conveyance of the sheet bundle without being driven by a driving roller driven by a motor.

  Various configurations can be considered for the conveying means 35. For example, as shown in FIG. 17A, the home position position of the cam 40 that rotates the conveying means 35 is detected by the sensor 400, and the home position May be controlled by an additional sensor or may be adjusted by pulse control of the motor M1. As shown in FIG. 17A, a driven roller 42 is disposed at a position where the roller 36 of the conveying means 35 faces, and a sheet bundle is sandwiched between the driven roller 42 and the roller 35 and pressurized by the elastic material 43 to be conveyed. Giving power. Further, as the paper thickness of the sheet bundle PB increases, a conveyance force, that is, a pressurizing force is required. Therefore, the roller 36 of the conveyance member 35 is driven via the elastic member 43 and the cam 40 as shown in FIG. The pressing force may be adjusted by the pressing angle of the cam 40.

  Further, as shown in FIGS. 21A and 21B, a discharge roller 56 may be used instead of the driven roller 42 as a roller opposed to the roller 36 of the conveying means 35. The nip position with the roller 56 is in the vicinity of a contact position where the conveyance locus line D1 of the sheet bundle PB and the concentric circle C1 of the discharge roller 56 are in contact with each other. The conveyance path for conveying the sheet bundle PB from the edge binding processing tray F to the saddle stitching processing tray G is composed of a discharge roller 56 and a guide member 44 on the side opposite to the discharge roller 56, and the guide member 44 is centered on a fulcrum 45. The drive is transmitted from the bundle branching drive motor 161. The home position of the guide member 44 is detected by the sensor 401. Further, the conveyance path for conveying the sheet bundle from the end binding processing tray F to the shift tray 202 as the stacking means is such that the guide member 44 is rotated around the fulcrum 45 as shown in FIG. And the guide plate 46 form a conveyance path.

Further, as shown in FIGS. 22 and 23, the roller 36 rotates and rotates in the same direction with respect to the conveyance direction C of the sheet bundle PB, as shown in FIGS. (FIG. 22) or may be rotated (FIG. 23) from the direction opposite to the conveyance direction C.
Further, as shown in FIG. 24, the pin 40a of the cam 40 for adjusting the pressing force of the roller 36 to the sheet bundle PB and the support shaft 36a of the roller 36 are connected by a spring 43 to adjust the pressing force of the roller 36. You may make it do.

(3) Sheet Folding and Saddle Stitching Processing Next, the center folding processing and the saddle stitching processing by the sheet post-processing unit device PD of this embodiment will be described.
<Folding process>
The sheet bundle PB conveyed to the processing tray G in a state in which the leading end PB1 and the trailing end PB2 of the sheet bundle PB are aligned from the processing tray F is sheeted by the folding plate 74 disposed in the processing tray G. The folding mechanism of the folding plate 74 will be described with reference to FIGS. 24A and 24B.
As shown in FIG. 25A, the folding plate 74 is supported by fitting the elongated holes 74a to the two pins 80 standing on the front and rear side plates, and the shaft 74b and the link arm 76 are connected to each other. The long hole portion 76b is fitted, and the folding plate 74 reciprocates left and right in FIG. 25 when the link arm 76 swings around the fulcrum 76a. The long hole portion 76 c of the link arm 76 and the shaft portion 75 b of the folding plate driving cam 75 are fitted, and the link arm 76 swings by the rotational movement of the folding plate driving cam 75. The folding plate driving cam 75 is rotated by the folding plate driving motor 166 in the direction of arrow O in FIG. The stop position is determined by detecting both end portions of the half-moon shaped shielding portion 75a by the folding plate HP sensor 325.

  FIG. 25A shows the home position position of the folding plate 74 completely retracted from the sheet bundle accommodation area of the processing tray G. FIG. When the folding plate drive cam 75 is rotated in the direction of arrow O, the folding plate 74 moves in the direction of arrow M and protrudes into the sheet bundle accommodation area of the processing tray G. FIG. 25B shows a position where the folding plate 74 is pushed into the nip of the folding roller 81 in the center of the sheet bundle PB of the processing tray G. When the folding plate drive cam 75 is rotated in the direction of arrow P, the folding plate 74 moves in the direction of arrow N and retracts from the sheet bundle accommodation area of the processing tray G.

<Saddle stitching>
The operation in the saddle stitch binding mode will be described below with reference to FIGS. In addition, although the example which employ | adopted the structure different from the conveyance direction change means shown in above-mentioned FIG. 17 as a conveyance direction change means of the sheet bundle PB shown in this FIG. 26 is shown, it is fundamentally processing tray. The method for changing the conveyance direction of the sheet bundle PB from F to the processing tray G is the same. That is, in this example, as shown in FIGS. 26 (B), (C), and (D), the sheet bundle PB that has been lifted up the conveyance path J by the discharge claw 52a of the discharge belt 52 is a pressure roller 57 at the tip. The movable guide 55 is transported by the branch guide plate 54 that is rotatably attached and the discharge roller 56 that is driven to rotate, and the movable guide 55 that is rotatably attached to the shaft center 56 a of the discharge roller 56 is rotated along the movable guide 55. And is transferred to the processing tray G.
After the sheet bundle PB is temporarily aligned on the processing tray F, as shown in FIG. 26D, the sheet bundle front end PB1 is sandwiched between the discharge roller 56 and the pressure roller 57, and the branch guide plate 54 and the movable guide 55 Is rotated again by the discharge claw 52a and the discharge roller 56 so as to pass the path guided to the processing tray G. The discharge roller 56 is provided on the drive shaft of the discharge belt 52 and is driven in synchronization with the discharge belt 52.

Thereafter, the sheet is conveyed by the discharge claw 52a until the trailing edge PB2 of the sheet bundle passes through the discharge roller 56, and further to a position where the leading end PB1 of the sheet bundle PB contacts the movable trailing edge fence 73 as shown in FIG. It is conveyed by the bundle conveying upper roller 71 and the bundle conveying lower roller 72. At that time, the stop position of the movable rear end fence 73 differs depending on the size of each sheet bundle PB in the conveying direction, and is waiting. When the sheet bundle front end PB1 comes into contact with and stacks on the movable rear end fence 73 waiting, the sheet bundle PB temporarily aligned on the processing tray F is moved to the movable rear end fence 73 as shown in FIG. The sheet bundle PB may be misaligned before being stacked, and the final alignment needs to be performed by the trailing edge hitting claw 251. Therefore, the pressure of the bundle conveying lower roller 72 is released, The rear end PB2 of the sheet bundle PB is hit with the rear end tapping claw 251 to finally align the conveyance direction.
Immediately after that, final alignment in the width direction is performed by the saddle stitching upper jogger fence 250a and the saddle stitching lower jogger fence 250b, and the center is bound by the saddle stitching stapler S2. Here, the movable rear end fence 73 is positioned by pulse control from the movable rear end fence HP sensor 322, and the rear end tapping claw 251 is positioned by pulse control from the rear end tapping claw HP sensor 326.

  As shown in FIG. 27G, the saddle-stitched sheet bundle is carried upward along with the movement of the movable rear end fence 73 while the pressure of the bundle conveying lower roller 72 is released, and thereafter, FIG. As shown in FIG. 27 (H), the vicinity of the stitched needle portion is pushed by the folding plate 74 in a substantially right angle direction and guided to the nip of the opposing folding roller 81. The folding roller 81 rotating in advance performs folding on the center of the sheet bundle PB by pressure-conveying the sheet bundle PB. Here, since the saddle stitched sheet bundle PB moves upward for folding processing, the sheet bundle PB can be reliably conveyed only by moving the movable rear end fence 73. If the sheet bundle PB is moved downward for the folding process, the movement of the movable rear end fence 73 alone is not reliable, and another means such as a conveyance roller is required. It becomes complicated. However, in this embodiment, the folding process is performed at the center of the sheet bundle PB by the folding plate 74 and at the same time, the central portion of the sheet bundle PB folded into the folding roller 81 is conveyed, so that the sheet bundle PB is moved downward. Therefore, the central portion of the sheet bundle PB can be appropriately conveyed to the position of the folding plate 74 only by conveying the sheet bundle PB upward.

  As shown in FIG. 27I, the folded sheet bundle PB is strengthened by the second folding roller 82 and discharged to the lower tray 203 by the lower paper discharge roller 83. At this time, when the sheet bundle rear end PB2 is detected by the folding portion passage sensor 323, the folding plate 74 and the movable rear end fence 73 are returned to the home position, and the pressurization of the bundle conveying lower roller 72 is restored. In preparation for feeding the sheet bundle PB. If the next job is the same sheet size and the same number of sheets, the movable rear end fence 73 may again move to the position of FIG.

As described above, in the sheet post-processing unit device according to the present embodiment, the following discharge forms (A) to (E) can be taken according to the post-processing mode.
(A) Non-staple mode a: The paper is discharged to the upper tray 201 through the transport path A and the transport path B.
(B) Non-staple mode b: The paper is discharged to the shift tray 202 through the transport path A and the transport path C.
(C) Sort, stack mode: The paper is discharged to the shift tray 202 through the transport path A and the transport path C. At that time, the sheets to be discharged are sorted by the shift tray 202 swinging in the direction orthogonal to the paper discharge direction at every section separation.
(D) Staple mode: alignment and binding are performed in the processing tray F through the transport path A and the transport path D, and the paper is discharged to the shift tray 202 through the transport path C.
(E) Saddle-stitch binding mode: alignment is performed on the processing tray F via the conveyance path A and the conveyance path D, and further, saddle stitching is performed on the processing tray G, center folding is performed, and the sheet is discharged to the lower tray 203 through the conveyance path H. The

  (A) The operation in the non-staple mode a will be described below. The sheet P distributed from the conveyance path A by the branching claw 15 is guided to the conveyance path B and discharged to the upper tray 201 by the conveyance roller 3 and the upper discharge roller 4. Further, the state of paper discharge is monitored by an upper paper discharge sensor 302 that is disposed in the vicinity of the upper paper discharge roller 4 and detects the discharge of the sheet P.

(B) The operation in the non-staple mode b will be described below. The sheet P sorted by the branching claw 15 and the branching claw 16 from the conveyance path A is guided to the conveyance path C and discharged to the shift tray 202 by the conveyance roller 5 shift discharge roller 6. Further, the state of paper discharge is monitored by a shift paper discharge sensor 303 which is disposed in the vicinity of the shift paper discharge roller 6 and detects the discharge of the sheet P.
(C) The operation in the sort and stack modes will be described below. (B) The same transport and discharge as in the non-staple mode b is performed. At that time, the sheets to be discharged are sorted by the shift tray 202 swinging in the direction orthogonal to the paper discharge direction at every section separation.

(D) The operation in the staple mode will be described below. The sheets distributed from the conveyance path A by the branch claw 15 and the branch claw 16 are guided to the conveyance path D and are discharged to the processing tray F by the conveyance roller 7, the conveyance roller 9, the conveyance roller 10, and the staple discharge roller 11. In the processing tray F, the sheets P sequentially discharged by the paper discharge roller 11 are aligned, and when the predetermined number of sheets is reached, the end surface binding stapler S1 performs the binding process.
Thereafter, the bound sheet bundle PB is conveyed downstream by the discharge claw 52 a and discharged to the shift tray 202 by the shift discharge roller 6. Further, the state of paper discharge is monitored by a shift paper discharge sensor 303 which is disposed in the vicinity of the shift paper discharge roller 6 and detects the discharge of the sheet.

  The above operation is operated by a computer built in the sheet post-processing unit apparatus, and its block diagram is shown in FIG. As shown in FIG. 28, the control means 350 is a microcomputer having a CPU 360, an I / O interface 370, etc., and each switch of a control panel of the image forming apparatus main body (not shown) and each sensor such as a paper surface detection sensor 330. Are input to the CPU 360 via the I / O interface 370. The CPU 360 drives the tray lifting / lowering motor 168 for the shift tray 202, the discharge guide plate opening / closing motor 167 for opening / closing the opening / closing guide plate, the shift motor 169 for moving the shift tray 202, and the tapping roller 12 based on the input signal. The tapping roller motor 156, the solenoids such as the tapping SOL 170, the conveying motor that drives each conveying roller, the discharging motor that drives each discharging roller, the discharging motor 157 that drives the discharging belt 52, and the stapler that moves the end binding stapler S1. A moving motor 159, an oblique motor 160 that obliquely rotates the end-face binding stapler S1, a jogger motor 158 that moves the jogger fence 53, a bundle branching drive motor 161 that rotates the guide member 44, and a conveyance roller that conveys the bundle are driven. Bundle conveying motor 162, movable rear end fence 7 Rear end fence moving motor 163 for moving the folding plate drive motor 166 to move the folding plate 74, controls the driving of such folding roller driving motor 164 for driving the folding rollers 81. A pulse signal of a staple transport motor 155 (not shown) that drives the staple discharge roller is input to the CPU 360 and counted, and the hitting SOL 170 and the jogger motor 158 are controlled according to this count.

1 is a diagram illustrating a schematic configuration of an image forming apparatus according to an embodiment of the present invention. FIG. 5 is a perspective view showing a shift tray swing mechanism used in the sheet post-processing unit device of the image forming apparatus according to the embodiment of the present invention. FIG. 4 is a perspective view showing a vertical movement mechanism of a shift tray used in the sheet post-processing unit device of the image forming apparatus according to the embodiment of the present invention. FIG. 5 is a perspective view illustrating a rotation mechanism of an opening / closing guide plate used in the sheet post-processing unit device of the image forming apparatus according to the embodiment of the present invention. FIG. 5 is a perspective view showing a mechanism of a processing tray F used in the sheet post-processing unit device of the image forming apparatus according to the embodiment of the present invention. It is a side view which shows the paper distribution state of the sheet | seat of FIG. FIG. 6 is a front view excluding the sheet P, the hitting roller, and the staple discharge roller of FIG. 5. FIG. 7A is a diagram illustrating an arrangement relationship between the leading edge hitting and the discharge claw used in the sheet post-processing unit device of the image forming apparatus according to the embodiment of the present invention, and FIG. (B) is a diagram showing a retracted state of the tip hit, (C) is a diagram showing a state in which the sheet bundle is conveyed by the discharge claw, (D) is a diagram showing a state in which the tip hit follows the release claw, and (E) is a tip. FIG. 5F is a diagram illustrating a state where the tap is at the home position, and FIG. 5F is a diagram illustrating a state where the leading edge moves the sheet leading edge downward. FIG. 3 is a perspective view showing a drive mechanism of a discharge belt used in the sheet post-processing unit device of the image forming apparatus according to the embodiment of the present invention. FIG. 2A is a side view illustrating a leading edge striking mechanism used in the sheet post-processing unit device of the image forming apparatus according to the embodiment of the present invention, and FIG. It is a figure which shows the state to justify FIG. 6 is a side view showing a mechanism of a rear end pressing lever used in the sheet post-processing unit device of the image forming apparatus according to the embodiment of the present invention. 11A and 11B are views showing the positional relationship between the rear end presser lever and the stapler as viewed from the X direction in FIG. 11, wherein FIG. 11A is a diagram showing the home position of the rear end presser lever, and FIG. FIG. 6 is a diagram showing the arrangement relationship of rear end presser levers when stapling is performed. FIG. 13C is a diagram illustrating the positional relationship between the trailing edge pressing lever and the stapler in FIG. 12, and FIG. 13C is a diagram illustrating the positional relationship between the trailing edge pressing lever when stapling is performed at the trailing edge of the center of the sheet bundle. FIG. 8B is a diagram illustrating the arrangement relationship of the rear end pressing lever when stapling is performed at the rear end of the sheet bundle in the back of the machine. FIG. 4 is a perspective view illustrating a lateral movement mechanism of a stapler used in the sheet post-processing unit device of the image forming apparatus according to the embodiment of the present invention. It is a perspective view which shows the rotation mechanism of the stapler of FIG. FIG. 5 is a flowchart illustrating alignment and stapling processing used in the sheet post-processing unit device of the image forming apparatus according to the exemplary embodiment of the present invention. FIG. 7 is a diagram illustrating a mechanism for changing the sheet bundle conveyance direction used in the sheet post-processing unit device of the image forming apparatus according to the exemplary embodiment of the present invention, and (A) is a diagram illustrating the mechanism when the sheet bundle is not conveyed; FIG. 5B is a diagram illustrating a state immediately before the sheet bundle is conveyed to the rollers and the driven roller. FIG. 18C is a diagram illustrating a mechanism for changing the sheet bundle conveyance direction shown in FIG. 17, and FIG. 17C is a diagram illustrating a mechanism for changing the sheet bundle to the processing tray G, and FIG. It is a figure which shows the change mechanism in a case. FIG. 10 is a diagram illustrating a relationship between a sheet bundle thickness and a distance between a discharge roller and a pressure roller in a sheet bundle conveyance direction changing mechanism used in a sheet post-processing unit device of an image forming apparatus according to another embodiment of the present invention. is there. It is a figure which shows the modification of the pressure roller of FIG. FIG. 20A is a diagram illustrating a nip state of a sheet bundle in the sheet bundle conveyance direction changing mechanism in FIG. 19, and FIG. 19A is a diagram illustrating a state when the sheet bundle is conveyed to the processing tray G, and FIG. FIG. FIG. 18 is a diagram illustrating another embodiment of the sheet bundle conveyance direction changing mechanism of FIG. 17. FIG. 18 is a diagram illustrating another embodiment of the sheet bundle conveyance direction changing mechanism of FIG. 17. FIG. 20 is a diagram illustrating another embodiment of the sheet bundle conveyance direction changing mechanism of FIG. 19. 2A and 2B are diagrams illustrating a left-right movement mechanism of a folding plate used in the sheet post-processing unit device of the image forming apparatus according to the embodiment of the present invention. FIG. It is a figure which shows the state in the case of retracting | folding a folding plate. FIG. 8 is a diagram illustrating a sheet bundle conveyance direction changing mechanism according to another embodiment used in the sheet post-processing unit device of the image forming apparatus according to the embodiment of the present invention. FIG. FIG. 4B is a diagram illustrating a state in which the sheet bundle is aligned with the rear end fence, FIG. 5C is a diagram illustrating a state in which the sheet bundle is conveyed by the discharge claw, and FIG. 4D is a diagram in which the sheet bundle is conveyed to the processing tray G. The figure which shows a state, (E) is a figure which shows the state which stacked | stacked the sheet | seat bundle on the movable rear end fence. 26A and 26B are diagrams illustrating a sheet bundle saddle stitching process and a center folding process using the sheet bundle conveyance direction changing mechanism of FIG. 26, wherein FIG. 26F is a diagram illustrating the sheet saddle stitching process, and FIG. FIG. 5H is a diagram illustrating a state in which the sheet is conveyed to the half-fold plate, FIG. 8H is a diagram illustrating a state in which the sheet bundle is folded in half, and (I) is a diagram illustrating a state in which the folded sheet bundle is conveyed. FIG. 3 is a block diagram of control means for operating the sheet post-processing unit device of the image forming apparatus according to the embodiment of the present invention.

Explanation of symbols

  P sheet, P1 sheet leading edge, P2 sheet trailing edge, PB sheet bundle, PB1 sheet bundle leading edge, PB2 sheet bundle trailing edge, PD sheet post-processing unit device, PR image forming unit device, A, B, C, D, E, J transport path, F staple processing tray, G saddle stitching, center folding processing tray, 44 guide member, 51 rear end fence, 52 discharge belt, 52a discharge claw, 53 jogger fence, 54 branch guide plate, 55 movable guide, 56 discharge Roller, 57 Pressure roller, 64 Substrate, 511 Tip tapping belt, 512 Tip tapping, 512a Support portion, 512b Support point, 512c Tip tapping portion, 512d Elastic member

Claims (6)

A conveying unit that conveys the sheet; a stacking tray that stacks the sheet conveyed to the conveying unit; and an alignment member that abuts and aligns the leading end of the sheet stacked on the stacking tray in the sheet conveying direction. A sheet processing apparatus including a discharge member that discharges the bundle of sheets in contact with the rear end of the sheet conveyance direction ,
The alignment member is provided on the alignment belt so as to be able to circulate between a sheet receiving position of the stacking tray and a retracted position on the back side of the stacking tray,
The discharge member is provided on a discharge belt that moves in a direction of discharging a sheet,
While the sheet bundle is being discharged by the discharge member, the alignment member is moved from the rear end side of the sheet bundle to the receiving position so that the sheet conveying unit can receive the sheet conveyed to the stacking tray. A sheet processing apparatus. The sheet processing apparatus according to claim 1,
The alignment belt is an endless belt stretched on the stacking tray, and the alignment member is circulated between the sheet receiving position and the retracted position by rotation of the alignment belt. Sheet processing apparatus. In the sheet processing apparatus according to claim 1 or 2,
The sheet processing apparatus according to claim 1 , wherein a moving speed of the alignment belt is equal to or lower than a sheet discharge moving speed of the discharge belt . The sheet processing apparatus according to any one of claims 1 to 3,
The sheet processing apparatus, wherein the alignment member includes a pressing unit that presses a leading end of the sheet bundle during alignment. The sheet processing apparatus according to claim 4, wherein
The sheet processing apparatus, wherein the pressing means is an elastic member.   An image forming apparatus comprising the sheet processing apparatus according to claim 1.

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